1. Technical Field
The present invention relates generally to digital computers; and more particularly to a method and apparatus for efficient derivation of modulo arithmetic for frequency selection in wireless interface devices coupled to digital computers.
2. Related Art
Wireless communication technology has advanced rapidly over the past few years. One of the most promising areas for the use of wireless technology relates to communications between input/output devices and their “host” computers. For example, wireless keyboards and mice now couple via wireless connections to their host computers. These “wireless” input devices are highly desirable since they do not require any hard-wired connections with their host computers.
Many current wireless devices communicate with the host computer by implementing a frequency hopping scheme as defined in the “Bluetooth” Specification Version 1.1, November, 2000, which by this reference is incorporated for all purposes. The Bluetooth specification defines a frequency selection module having an output that constitutes a pseudo-random sequence having either 79 hops or 23 hops, depending on the specific implementation. The pseudo-random frequency hopping scheme is implemented using a modulo arithmetic derivation for selecting the frequencies to be used. Current methods for calculating the modulo arithmetic solution for the frequency hopping are comparatively complicated and, therefore, processor intensive and consume a significant amount of power. This is undesirable in wireless devices that rely on battery power. Thus, there is a need in the art for a method and apparatus for efficiently calculating the modulo arithmetic solution for frequency hopping in transceivers used by wireless input devices to communicate with their host computers, thereby providing more efficient operation and extended operating time when the device is operating on battery power.